The invention relates to a catheter for providing a fluid connection with the small intestine, preferably for liquid supply, for example nutriment supply, to said intestine but also for diagnostics (injection of contrast agent for taking an X-ray of an intestine or taking samples of the testine contents or the mucous membrane), comprising a tube to be inserted into the small intestine via the stomach, having proximal and distal open ends and having inherent tendency of coiling over a predetermined length at the distal end thereof, and a guide displaceable in the tube from the proximal end thereof for straightening said predetermined length in order that said length is straightened during the actual insertion into the stomach.
A catheter of this type is used for post-operative nutriment supply via the intestine in order to replace intravenous nutriment supply which is more difficult to administrate but above all costs 5 to 10 times more and also is associated with substantial complications. The catheter is positioned at the distal end thereof in the small intestine, preferably in the upper part of jejunum, in the manner described in EP 0 278 97. The catheter having said normally coiled predetermined length thereof straightened by the guide being pushed into said length is inserted at the distal end thereof into the stomach through the nose or the oral cavity via the gullet and the esophagus, or also percutaneously. At following nutriment supply in the normal manner during a predetermined period the catheter is advanced from the stomach into the small intestine by the movements of the stomach and the peristaltic movements of the intestine because the coiled length of the catheter will be processed by the stomach and the small intestine in the same manner as the surrounding nutriment. Thus, the catheter is self-feeding. Usually the coiled length of the catheter should be located in the upper part of jejunum, and when this position has been reached the catheter is fixed such that it cannot be further advanced into the small intestine. Once located the distal end of the catheter will be held anchored in jejunum by the coiled length engaging the inside corrugated surface of the intestine. The purpose is thus to provide the greatest possible friction between the catheter and the intestine wall.
JP-A-08098889 relates to a catheter to be inserted into the internal organs of the body and is of the prior art type having a weight at the distal end thereof in order that the catheter can more easily be inserted and located in the correct position in the organs. The catheter according to said publication in a distal end portion thereof forming a guide has a row of a number of polyhedral bodies having a specific weight of 1 or more and enclosed by an elastic film so that the catheter at the outside thereof forms unevenness in order to be advanced by peristaltic convulsions of the organs. The advantage of this embodiment of the catheter is said to be that the insertion of the catheter and change of the direction thereof will be facilitated the pain felt by the patient at the same time being reduced.
The catheter described in EP 0 278 937 has been found to well satisfy the purpose thereof in practice. The catheter does not differ essentially from conventional nasoenteric silicone tubes and, therefore, the costs for manufacturing such a catheter will not be much higher than those for manufacturing silicone tubes. It has been found that the catheter has advanced into the small intestine in 4 to 6 hours after the insertion. After the insertion it will be kept in the position thereof in the upper part of jejunum until it is to be removed usually after seven days or so. The risk of the catheter being returned to the stomach prematurely is small because said length of the catheter having a tendency to coil efficiently prevents dislocation by engaging the inside surface of the small intestine. In about 95% of the cases in which the catheter has been used it has attained the intended position in the small intestine and has maintained that position.
The advancement of the catheter can be stimulated by the supply of Metoclopramide or Erythromycin but not all patients can stand these agents due to side effects connected therewith.
The purpose of the present invention is to further improve the catheter according to EP 0 278 937 regarding self-advancement without supply of said agents while maintaining a safe and even improved retainment of the catheter in the predetermined position, and for this purpose the catheter according to the invention has obtained the characterizing features of claim 1.